Aseptic valve assemblies are used in sterile process technology, for example in food technology, in order to be able to guide a product from a first product line into a second product line.
A generic valve assembly, installed in a system, is shown in FIG. 1. The valve assembly 1s is arranged between a first product line 2 and a second product line 3 and has a product valve 4. In the open state of the product valve, a fluid connection between the first product line 2 and the second product line 3 is connected through chamber 5 and inlet chamber 6 so that a product flow is possible between the product lines. Due to the two chambers 5 and 6, the product valve is also called a double chamber valve.
The system has a steam line 7, from which a first branch line 8 and a second branch line 9 branch off and lead to the valve assembly 1s. The first branch line 8 is connected with a steam valve 10, which is connected to the chamber 5. With the help of this steam valve 10, the chamber 5 is pressurizable intermittently with steam. The second branch line 9 is connected to a sequence valve 12, which is itself connected with the leak valve 11 and a disposal line 13.
In the case of finicky products, it is common, for additional security, to supply the leak valve 11, also called a side valve, on the product valve 4 with steam in order to eliminate the contamination risk from the atmosphere. Up until now, this has been realized via the additional sequence valve 12 designed as a shutoff valve at the leak outlet.
The disposal line 13 guides the fluid flow to a branch valve 14. The fluid flow can be switched to a condensate drain 15 by means of this branch valve 14, through which condensed steam can be supplied to a disposal device 16. Alternatively, the branch valve 14 can direct the fluid flow to a disposal valve 17 instead of the condensate drain 15. If the disposal valve 17 is opened in this circuit, the fluid flow is directed to the disposal device 16 by circumvention of the condensate drain 15.
A similar valve assembly is known from DE 203 17 882 U1. Steam valve 10 and leak valve 11 are shown in it. In order to simplify the representation, the sequence valve 12 and the details of the disposal branch are omitted.
A slightly different type of steam barrier is shown in EP 0 332 806 A2. Steam valve 10 and leak valve 11 are present, but the sequence valve 12 is replaced by a shutoff valve in the branch line 9, which is labeled with the reference number 15 in EP 0332 806 A2.